The present invention relates to an apparatus for sticking labels to containers such as bottles and cans, and, in particular, to a label sticking apparatus having a main body to which label application devices for applying labels to containers are detachably mounted.
It is a common practice to stick labels, which indicate contents, producers and distributors, onto containers such as bottles and cans after having them filled with contents. Such a label sticking apparatus for sticking labels to containers generally comprises a transporting device for transporting containers along a predetermined path, and at least one label application device disposed at a position of the predetermined path. Label application devices may be provided as many as the number of labels to be stuck to a container. Each label application device comprises a magazine for storing a quantity of labels, a label application drum for applying labels to containers, and a supply mechanism for supplying labels from said magazine to the label application drum one by one with gluing one side surface of the label.
Labels are required to be stuck to containers properly at desired positions, and, therefore, the drive of the label application devices must be synchronized with the drive of the container transporting device. In other words, the rate of rotation of the label application drum of each label application device must have a certain relationship with the travelling speed of the containers transported by the transporting device. In order to satisfy this requirement, it has conveniently been so structure that label application devices are driven by the driving source of the container transporting device. Such a structure is advantageous because it is simpler as compared with the case in which separate driving sources are provided for a container transporting device and a label application device. Moreover, provision of separate driving sources will require a mechanism for synchronizing the two entities, which indicates further complication in structure.
Meanwhile, even if use is made of a single driving source as in the prior art technique, there still remains disadvantages owing to the semi-permanently integrated structure between the container transporting device and the label application devices. For example, it is occasionally desired to change labels and containers to which the labels are to be stuck. If it happens, the customary apparatus will require elaborate adjustments, for example, for the label supply mechanism and the label application drum so that labels, when changed, may be properly stuck to the desired positions of a container. Such adjustments can be done by a skilled artisan only with an exorbitant amount of time. Furthermore, new labels might not fit to the existing label application devices because of their size or shape. Thus, if one wants to use new labels which are too big for the existing label application devices must purchase another label sticking apparatus designed especially for the new labels. Alternatively, the new labels must be disposed of. New labels are usually designed and used for new products with a view to attracting buyer's attention. However, since the prior art apparaus is not so flexible, label designing is necessarily limited.